oni vs os, What's the Difference?

Which to use

“oni” is a pronoun and “os” is an article - they look or sound alike but fill different roles in a sentence.

#49,618
“oni” frequency rank: #19
“os” frequency rank: 49637
confusion score

Side-by-Side Comparison

Feature	oni	os
Definition	pronome pessoal do caso nominativo da terceira pessoa do plural de gênero masculino pessoal, eles	usado para apontar um nome definido, único

Letter map: oni vs os

Shared letters muted; letters that set oni and os apart highlighted. Shared run: 1.

3 ch

oni

2 ch

Part-of-speech tell for oni / os

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: oni is apronoun and osanarticle. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 49637, derived from the frequency rank of both members and their visual similarity.

oni is recorded at frequency rank #49,618, classified as apron. os is at rank #19, tagged as anarticle, pronounced /uʃ/, /us/ (menos frequente); enfático: /oʃ/, /os/ (menos frequente).

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 49637, this pair ranks #15,348 of 75,631 scored Portuguese confusable pairs - among the most confusable pairs.

Orthographic DNA of oni vs os

Shared letters: o. Private to "oni": in. Private to "os": s.

"oni" · 3 letters · shape VCV · "os" · 2 letters · shape VC

Frequently Asked Questions

Do "oni" and "os" mean the same thing in a sentence?

No - they are not even the same part of speech. "oni" is a pronoun and "os" an article, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "oni" or "os"?

"os" is the more common of the two: it sits at frequency rank #19 in our Portuguese list, against #49,618 for "oni". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

You've compared "oni" and "os". Here's where to go from here.

Full dictionary entry for "oni" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "os" - compare definitions side by side with the headword page. Word entry
This pair ranks #15,348 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
"oni" and "os" also get mixed up with nearby pairs, the highest-scored neighbour is "oni vs ons". Nearby pair

Confusion rank #15,348 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.